


When You Mate With Merpeople, Always Bring A Water Bottle

by No1DigiBakuFan



Series: Mindbreak, Hypnotism and Monster Smut [1]
Category: Voltron: Legendary Defender
Genre: Aftercare, Alternate Universe - Merpeople, Anal Sex, Aphrodisiacs, Begging, Biting, Breeding Kink, Bulges, Cock Slut Lance (Voltron), Come Eating, Coming Untouched, Communication, Creampie, Fluff, Hair-pulling, Inspired by Fanart, M/M, Marathon Sex, Mating Cycles/In Heat, Merman Shiro, Mindbreak, Monster sex, Oral Sex, Possessive Sex, Praise Kink, Prostate Massage, Rimming, Xenophilia
Language: English
Status: Completed
Published: 2017-07-22
Updated: 2017-07-22
Packaged: 2018-12-05 13:27:40
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,846
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/11579004
Author URL: https://archiveofourown.org/users/No1DigiBakuFan/pseuds/No1DigiBakuFan
Summary: Lance is about to find out why that is true when his merman boyfriend calls him down to the cove in the early night.





	When You Mate With Merpeople, Always Bring A Water Bottle

**Author's Note:**

> Okay, there's some stuff in here I didn't know the tag for but basically Shiro does some merman magic thing to Lance's head and it ends up giving him an orgasm or two.
> 
> Everything is safe, sane and consensual.
> 
> Art link that inspired this: http://tetsarou.tumblr.com/post/163257396574/i-love-mermaid-aus-a-lot-especially-anything-that (VERY NSFW PICTURE)

Shiro anxiously waits in the shallow waters for Lance to arrive, heat starting to spread within him. He can't see him anywhere and his brain informs him he won't have long until his heat takes him. His instincts tell him it's not safe to be in such shallow waters, predator and unwanted mate could take him easily in these conditions, he wouldn't be able to fight-

"Shiro!"

Shiro breathes a sigh of relief as he watches Lance running down the beach towards their secret cove.

"Sorry I was late, it took a while to get the little ones to go to bed." Lance explains, "But when I heard your starfish calling, I came as fast as I could."

Shiro smiles at the small starfish on Lance's left ear, it's sister on Shiro's ear, "They were an excellent idea. Listen, I don't have much time, so I'll try to make this quick, but before I begin, I want to say something."

Lance nods, sitting cross legged in the sand, "Listening."

Shiro sees his legs spread wide, showing off Lance's package, considers if beaching himself is worth getting that cock in his mouth, "You don't have to do anything you don't want to, okay?"

Lance nods, eyebrows narrowed, "What's going on, Shiro?"

"To put it simply Lance, I'm in heat. Or about to go into heat." Shiro explains, "I've still got enough time to head for a cave to hide during that time but I was wondering if you'd be willing to help me out during it. Please?"

Lance is beat red, almost as red as Shiro was the first time he rehearsed this, "Yo-you want me to fuck you?! What if you get pregnant or something, I'm not ready to be a dad!"

"Lance, it's alright, I've done my research, there's practically zero chance of me getting pregnant from your human jizz and well," Shiro can't fight the blush anymore, a part of his heat coming on, "I'd be the one doing the fucking actually. As I said at the start, you don't have to do anything you don-"

"If you tell me to leave after hearing that, I'm gonna be on your dick in two ticks flat making you _keep_ me here." Lance states, walking into the water, "I wanna help you with this and frankly, it sounds hot, so... when do we start?"

Shiro swallows, "Now would be a really good time, actually."

Lance nods back, "Great, should I just-"

He yelps as Shiro yanks him into his lap, tongue in his mouth almost instantly, hands wandering all over his body. Lance moans at the attention and feels Shiro up too, running his hands on the tail when he can get at it, knowing how sensitive it is.

Shiro pulls back from the kiss, smirking, running his tongue along his lips, pupils narrowed into slits like a cat's, "You taste so good, love. You make me feel amazing, fitting perfectly into my body, like you were made to be here. Wouldn't you agree?"

Lance wiggles on the spot, harder much quicker than he'd ever been in his life and nods, the air thick with arousal, wanting to do anything to help ease the tension, "Yeah, uhh, what's happening? Getting that hard that fast isn't normal?"

Shiro blinks, "I'm afraid I must apologize Lance, it appears my heat's coming on a bit strong. But the purpose of it is to help a potential partner to get aroused quicker, so the night may last as long as possible. It can affect a partner’s mood and the general atmosphere of a situation."

Lance gulps, "So your ocean chemical things is giving me a extra quick boner?"

"Among a few other things, like flooding your system with what you'd probably call an aphrodisiac and well," Shiro flushes, "when we're like this we kind of... we play a bit with a mate's brain, impose perhaps different situations and make them seem real. I'll do my best not to do that or at least warn you, but it’s difficult to mate without pulling that one at least once. I should've warned you earlier, I'm sorry."

"Shiro." Lance calls.

Shiro looks him in the eye.

"You have a lap full of very hard Lance who is very interested in everything that just came out of your mouth, so if you please," Lance smirks, "lead the way."

Shiro blinks.

A smirk crawls across his face, "You really shouldn't have said that love."

"Make me regret it then. I dare you." Lance smirks back.

Shiro closes his eyes, "You asked for it."

Suddenly something _amazing_ explodes in Lance's brain and he groans, shifting on the spot, humping Shiro, desperate for release from the fire in his body, working it’s way between his thighs, making him ache with need, begging for more, _more_ , **_more_ **.

He arches his back, putting himself on display for his mate, looking pretty for his mate. Shiro grabs Lance’s hair and pulls, leaving Lance keening in his lap, scrapping for purchase on Shiro’s shoulders.

Shiro smirks, "Let's have a look inside that pretty little head now, shall we?"

Lance moans, "Please, please Shiro, I want it!"

Shiro chuckles and his eyes lock onto Lance's, flashing yellow all around.

Lance feels like Shiro's taken over every one of his senses and is stimulating them all, causing him the greatest pleasure he’s ever felt; the sounds he makes on Shiro's lap, the look on Shiro's face while Lance humps him, the feel of that powerful tail beneath him, the scent of sweetness that's coming from Shiro's heat, the taste of Shiro on his tongue. It all leads back to Shiro and the pleasure and the way it keeps building and building inside him.

Suddenly Lance knows exactly where he should be. He should be bouncing on Shiro's cock, driving the merman to pleasurable madness with anything Lance can use while getting fucked good like the filthy breeding hole he is, stuffed full of the merman's cum, make it drip down his thighs and ache in the morning-

Shiro laughs, "Well aren't you eager to please?"

Lance whimpers, grinding into Shiro's lap, "Shiro, I want your cock."

Shiro smirks at him, as if a lap full of squirming human couldn't affect him at all, "But you're still wearing those ridiculous human cloths, love. How can I give you my cock when you're hiding that beautiful body from view?"

Lance whines high in his throat, "Shiro-"

"You don't get so much as a look until you're naked." Shiro states, "Now strip."

Lance has never followed an order so quickly in his life, standing on legs weak with attraction, wanting to be as close to Shiro as possible, not this far away just because of some stupid pieces of cloth.

Shiro smirks and runs his eyes all over Lance's body, "Ohh Lance, the things you do to me. Just the sight of you is enough to work me up these days. All I could think about was how well your body would take my cock. I wanted it since we met, wanted to woke you open and onto my cock, make you whine and beg for it. There were so many times I wanted to take you right there on the beach. Fuck you and stuff you so full of my cum, making it drip on the sand."

Lance whimpers and calls out, "Shiro, I want it, please, I want your cock!"

No sooner had he finished, he’s in Shiro's lap again, making out sloppily while Shiro takes handfuls of his ass, spreading it, dipping fingers in every now and then, making Lance sing and shout in his lap, begging for more.

"If I had my way, I'd keep you like this everyday. You look so good, a perfect breeding hole." Shiro states, "I'd fill you up every single day, stuff you with my cum, how does that sound?"

Lance whimpers and whines, grinding into Shiro's stomach, drool running down his mouth, "I want it, I want your cock Shiro, give it to me, please!"

Shiro smirks, "Very well then."

He bites into Lance's shoulder to give him a nice hickey as Shiro's cock penetrates Lance.

Lance keens on it, arching his back, whimpering as he feels the small tip go further inside him, getting wider and wider. Lance knows somewhere in the back of his mind, Shiro's dick is bigger than any humans he's ever had. But he can hardly think about that because he finally has what he needs.

Shiro keeps slowly teasing his cock inside Lance and he feels so _fucking good_ . God he needs this. He needs Shiro’s cock. He’s a filthy breeding tool, a hole to be filled and fucked, over and over and Lance _loves_ it.

"Can you feel it Lance?" Shiro murmurs into his neck, "It's so small at the tip, but it gets wider and wider, it'll stuff you so full of my cum you'll bulge like a pregnant bitch. Would you like that?"

Lance moans and tries to buck back on Shiro's cock that's entering him far too slowly, smiling wide, "Yes, _yes_ , fuck me, breed me, use me!"

Shiro grins, "You know exactly where your place is, Lance, don't you? You're my little breeding toy for me to use however I please, for me to fill up every day, make you fall asleep with a belly full of my cum and wake up to a cock oh so eager to fill you up more."

Lance continues to smile, moaning and spreading his legs as wide as he can, "Yes, yes, your cum bucket, fuck me till I pass out, make me feel it for days!"

Shiro smirks, "That can be arranged."

He twists his cock just so to hit Lance right on the-

"SHIRO!" Lance screams, cumming from the one touch, clenching down tightly onto Shiro's cock, "FUCK ME, PLEASE!"

Shiro gets the rest of his cock in first, marveling at the beautiful sounds his Lance keeps making, Lance who keeps thrusting back on Shiro as if wanting more of Shiro's cock even thought that's all, Lance who's stomach is bulging from how big Shiro's cock is inside him, Lance who looks like he's completely lost his mind in the pleasure, smiling wide and moaning anytime he so much as glimpses his stomach, as if wishing it pregnant, full of Shiro’s guppies and cum.

Then he starts thrusting, scraping the tip of his cock against Lance's prostate on every drag, massaging it, never letting up on pleasing it.

Shiro moans, wrapping his arms tight around Lance, making him bounce in his lap, "You're so tight for me Lance, you feel so good on my cook, you were made to take it, weren't you?"

“So good!” Lance nods, still smiling over every moan, so happy that Shiro wants him, wants to use him like a _toy_ , fill his greedy hole full of cum again and again, "Shiro your cock is fucking amazing, I love it, I fucking love it!"

Shiro grunts as he picks up the pace of his thrusts, "Louder."

“I need your _cook_ , Shiro!” Lance lets out the loudest moan yet, more like a cry, marveling at how wonderful Shiro, thick and throbbing so deep inside him is all he’ll ever want, all he’ll ever need, ever again, "I want your _cock_ to _fuck me_ , Shiro, I want your cum!"

Shiro picks up the pace again, " _Louder._ "

Lance positively shrieks, still smiling, eyes rolling into the back of his head, "Fuck me, Shiro I want your _cook_ , I _need_ your cum-"

Shiro groans as he cums, "LANCE!"

Lance makes the most beautiful sound Shiro's ever heard as he cums, "SHIRO!"

As he cums, Lance’s stomach grows larger and Shiro’s head clears from the haze of his heat, a little. Shit, he better clean Lance up, make sure he’s okay. Shiro takes them nearer the shallowest part of the cove, pulls out and watches in awe as his cum dribbles down Lance’s ass, to his thighs, making an irresistible trail to-

Lance whines high in his throat and leans backwards, on the spreading himself open with one hand, letting more cum drip out of him, “Please, more, it’s not enough, I need more.”

“Shhhh…” Shiro whispers, placing a hand on Lance’s cheek. Lance nuzzles into it and Shiro’s heart swells, “Later, if you promise to be good and let me clean up. We can’t keep my Lance messy forever, can we?”

Lance shakes his head, “No.”

“Good boy.” Shiro kisses him, “Now just relax and let me make it better, okay?”

Lance moans softly and nods.

Shiro kisses him a final time, then dives down between Lance’s legs to start licking up his cum. He listens to Lance whine and cry out at every flick of his tongue over those lovely legs, thick thighs and round ass. By this point he has Lance’s legs over his shoulders, his hands molding and caressing the plump cheeks, pulling them apart while he licks his lips. Lance has a hand in his hair and it pulls in just the right ways.

“Shiro it’s so good, stop or I’ll cum again, please, I wanna save that for when you’re inside me, pretty please?” Lance whines high in his throat, trying to grind down.

Shiro chuckles, “Don’t worry love. My heat can keep you hard and wanting all night long if I feel like it.”

Then he spreads Lance’s cheeks and kisses his rim.

“SHIRO!” Lance screams, “ _Fuck_ , what did that feel so good?!”

Shiro chuckles and starts lapping at Lance’s rim, cleaning up the traces of his cum and then just… exploring. He takes his time, licking Lance in different patterns and waves, repeating something when he saw it bring out a particularly wonderful reaction. Repeated kitten licks on the outside of Lance’s rim seem to bring out the most delicious sounds from him.

Shiro wonders… and gives it a try-

“OH MY GOD!” Lance screams, throwing his head back, squirming, moaning as he thrashes, cumming once more, “FUCK, FUCK, FUCK, FUCK, FUCK-”

Shiro continues to flick his tongue in and out Lance’s rim, used to the taste of his own cum and addicted to the taste of Lance’s essence so near him, so strong, so delicious. He closes his lips around the rim and moans.

“SHIRO!” Lance moans, legs locking behind him, only staying still thanks to Shiro’s iron grip on his ass.

Shiro internally smirks and decides to suck.

Lance gasps harshly.

Shiro alternates between sucking and moaning, swirling his tongue around now and then, trying to spread Lance wider, get in deeper, get him to-

“SHIRO!” Lance screams as he cums again, grasping helplessly onto the sand, “No more, please, I won’t survive, I’m spent, please Shiro-”

Shiro removes himself and looks at the mess he’s made.

Lance is panting, the sand near his hands covered in gouges as if he’d tried to hold onto the ground, a faint outline of his frame from all the wriggling. His pupils have completely taken over his eyes, his face, ears and neck completely red with a dusting of a blush on his collarbone. He pants as if he ran for miles, there’s tear stains on his cheeks (Shiro should’ve noticed him crying sooner, shit, what if he’s hurt his beautiful mate?) and his stomach is covered in cum of varying degrees of wetness.

Shiro tries to reel in as much of his heat as he can, trying to get it to release it’s hold on Lance a little, “Lance? Do you need to stop?”

Lance manages a nod.

“I’ve got some food and a fresh water bottle nearby. Do you need it?”

Another nod.

“I’m still right in the cove, even if you can’t see me love. I’m right here.”

He presses a kiss to Lance’s forehead and beaches himself, crawling towards the ring of stones he’d used to mark the place earlier. He’d have to thank Hunk again for helping him make sure Lance would get what he needs.

Shiro claws at the sand until he reaches a box. He pulls it out of the sand and starts dragging himself towards Lance. Once his tail is in the water again, he opens the box to find a bunch of sandwiches for Lance, a few fish for him, a warning note from Hunk (“If you hurt him I’ll give every photograph we have of you to the national news”-Hunk) and a bottle of clean drinking water.

Shiro sets the items down, outside of the tides reach and shifts towards Lance, calling softly, “Lance, are you still there?”

Lance manages a groan.

“That’s it, buddy. Think you can wake up a little more? I’ve got Hunk made sandwiches on hand?” Shiro calls, reaching out, wrapping his arm around Lance’s shoulders.

Lance manages a small nod and then collapses his head on Shiro’s shoulder.

Shiro tries not to “coo” when he’s more or less sapped his mate’s soul out of his body.

“What do you want? Options are ham, jam or cheese?” Shiro grabs the sandwiches.

Lance groans into Shiro’s shoulder.

Shiro sets them down and grabs the water instead, “You need a drink before you can talk?”

Lance nods.

“I’m here, love.” Shiro calls, opening up the bottle and offering it near Lance’s lips, “Think you can take it from here or do you need my help?”

Lance pokes Shiro in the thigh.

“Okay then.” Shiro presses the bottle to Lance lips, “Drink up, love.”

He tilts it until it starts going into Lance’s mouth. He keeps it at that angle and when Lance doesn’t push away, he tilts it a little higher again and keeps the angle for Lance to drink.

It doesn’t take long for Lance to decide he’s had enough water when one drop trickles past his lips and he squeezes Shiro’s thigh.

Shiro caps it, “How are you feeling, love?”

Lance chuckles, “Like I took way too much dick for a normal human to handle. I really hope there’s some morning after cream or something in there to help with my muscles, I’m gonna be so sore.”

Shiro blushes as he grabs the jam sandwich, “Sorry for that. Jam?”

Lance nods and unwraps it, eating it up quickly.

Shiro can’t help but smile as he watches Lance eating, getting a bit of jam on his cheek. He dips his hand in the sea water and wipes at it, trying to get rid of the stickiness.

Lance laughs, “And I was hoping you’d kiss it away.”

“I think if my lips come into contact with you again, I won’t be able to stop myself.” Shiro flushes, “I can get over the worst of my heat when there’s help on hand but I still, well… Yeah.”

Lance raises an eyebrow teasingly, “That doesn’t make any sense babe. Use your words.”

Shiro groans, “I’m still in heat and I know if I kiss you I’m gonna lose control again. I can hardly get my cock to stay sheathed with you sitting so close to me, I should have more control over my body, damnit.”

Lance shrugs, “Ehh, control’s for the overrated. Besides, you as a wild, ravenous beast is hot as fuck and that shit you did to my head? That was _the_ best orgasm of my life.”

Shiro flushes and hides his face in his hands, “Lance please, stop torturing me with memories, keeping it down is hard enough. I can’t keep you here all night until the heat’s been fucked out of me.”

Lance pouts, whining, “But why not? It’s Saturday tomorrow, I can stay in and recover or I can spend the day with you and recover!”

Shiro looks at his lap, still red, “It’d be selfish and you hardly survived what just happened! That wasn’t exactly tame, but it’s not my worse either Lance and I… I don’t wanna hurt you. When you’re in that state my heat gets you in, pain becomes the very last thing on your mind, unless it excites you sexually and that’s the only shit that gets through. Everything else is white noise and I don’t want to accidentally damage you by being too rough. Besides I know how badly you need a full night’s sleep.”

Lance chuckles, “I think my beauty regimen can handle a night off. Shiro…”

Shiro looks at Lance.

Lance smiles and cups his face, “I know you won’t hurt me. You’re always so careful with me during regular sex and I honestly don’t trust anyone else in the world to look after me as well as you do,” Lance raises a hand, pointing as he blushes, “in this particular kind of situation, I mean, I’m pretty sure your cooking’s the only thing about you that could hurt me! The point I’m trying to get across is, you won’t hurt me. That was the best fucking of my life Shiro, you’ve ruined me for every other man!” Lance sighs as if watching a tragedy, arm over his eyes, “None of them will ever fuck me like you do, I’ll never be able to go back to human sex, it just can’t make me cum the way you do.”

Shiro finds himself laughing, “Stop being over dramatic, I’m sure there must be at least one human out there who could fuck you better than me.”

“No, no, no, no, nope, I’m only ever fucking with you and never gonna find that out, nope, it’s not gonna happen.” Lance states, smugly.

Shiro rolls his eyes.

“If you’re really that afraid you’ll hurt me, we can stop. I can go home and you can deal with your heat on your own if you want, I won’t force myself upon you if I can’t make you feel good.” Lance declares, “But I personally know you wouldn’t ever hurt me during sex, no matter how heat crazed we both get. It’s not selfish to fuck me through the night when I want it too. We can take breaks to make sure I survive the night. And personally, I’d like to see you do your worst. But in the end, the decision is yours, Shiro. Do I stay, or do I go?”

Shiro stares into Lance’s beautiful eyes, unable to believe all that he’s hearing.

Lance knows he won’t hurt him in sex (Shiro’s starting to believe that might be true).

Lance wants to stay (Shiro can’t believe that’s true).

He’s giving Shiro the choice first and foremost (Another thing he can’t believe).

Shiro feels tears well up in his eyes and he holds Lance close to him, warping both his arms around this beautiful, amazing boy who he can’t believe is in his life, rubbing his tail fins against human feet. He hides his eyes in Lance’s hair and takes a deep breathe.

“Thank you, Lance.” Shiro whispers.

Lance slowly wraps his arms around Shiro’s lower back and hugging his tail between his legs, rubbing his toes over his fin tails.

“For what?” Lance wonders.

Shiro smiles.

“For loving me.”


End file.
